A missing protein (MP) is an unconfirmed genetic sequence for which a protein product is not yet detected. Currently, MPs are tiered based on supporting evidence mainly in the form of protein existence (PE) classification. As we discuss here, this definition is overly restrictive because proteins go missing in day-to-day proteomics as a result of low abundance, lack of sequence specificity, splice variants, and so on. Thus, we propose a broader functional classification of MPs that complements PE classification, discuss major causes, and examine three corresponding solution tiers: biological, technical, and informatics. We assert that informatics-driven solutions would have a major role in resolving the MP problem (MPP).

蛋白质丢失（MP）是未经确认的遗传序列，尚未检测到蛋白质产物。当前，国会议员基于支持证据进行分层，主要以蛋白质存在（PE）分类的形式进行。正如我们在这里讨论的那样，该定义过于严格，因为蛋白质的日常蛋白质组学由于缺乏，不具有序列特异性，剪接变体等原因而在日常蛋白质组学中丢失。因此，我们提出了MP的更广泛的功能分类，以补充PE的分类，讨论了主要原因，并研究了三个相应的解决方案层：生物学，技术和信息学。我们认为，信息学驱动的解决方案将在解决MP问题（MPP）中发挥重要作用。